Large-Scale, GPU-Enhanced DFTB Approaches for Probing Multi-Component Alloys

S.I. Allec, N.V. Ilawe, and B.M. Wong
University of California, Riverside,
United States

Keywords: density functional theory, materials screening, structural materials

Summary:

This presentation will give an overview of our recent work on developing, analyzing, and introducing (1) accurate intermolecular potentials and (2) GPU enhancements to the density functional tight binding (DFTB) approach for high-throughput ab initio molecular dynamics calculations of multi-component alloys at elevated temperatures. Together, these advancements have enabled a new computational capability for accurately and efficiently assessing structural performance of materials with large-scale calculations that need significantly less time than current quantum computational methods. While classical molecular dynamics can handle hundreds of thousands of atoms, it cannot provide a first-principles based description of large, multi-component alloys at the predictive quantum level. At the other extreme, conventional Kohn-Sham DFT methods can probe the true quantum nature of chemical systems; however, these methods cannot tackle the large sizes relevant to these multi-component systems. The DFTB-based ab initio molecular dynamics approach (coupled with our in-house GPU capabilities for enhanced speed) used in this project provides a viable approach for probing these large systems at a quantum level of detail that is significantly faster than current first-principle methods Collectively, the capabilities developed in this project directly respond to initiatives that rely on structural materials by (1) enabling accurate and efficient predictions and (2) bringing a fundamental understanding of structural interactions in these complex systems at elevated temperatures.